U.S. Pat. No. 3,674,836, which is herein incorporated by reference, disclosed certain 2,2-dimethyl-.omega.-aryloxyalkanoic acids and salts and ester thereof.
The compounds disclosed in the above United States Patent are useful in regulating blood lipid levels and afford protection from coronary heart disease. Thus, they are useful in the treatment of atherosclerosis. Particularly valuable as a lipid regulating agent is gemfibrozil chemically known as 5-(2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid.
U.S. Pat. Nos. 3,674,836, 4,126,637 and 4,665,226 disclose various processes for preparing the aforementioned compounds. The processes disclosed in U.S. Pat. Nos. 3,674,836 and 4,126,637 utilize metalated carboxylic acids.
The object of the present invention is an improved process for preparing the compounds described above by using a novel synthesis.
Further, we have unexpectedly found that metalated zinc and magnesium carboxylates form homogeneous solutions in nonpolar solvents. The present process is more conveniently performed in higher yields than the prior art processes. Thus, the present process is amenable to large-scale synthesis.